diff --git a/docs/release-notes.md b/docs/release-notes.md
index 64f6368d..93e80266 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -17,6 +17,7 @@
   * Fixed 'unknown mod' deprecation warnings showing the wrong stack trace.
   * Fixed `e.Cursor` in input events showing wrong grab tile when player using a controller moves without moving the viewpoint.
   * Fixed incorrect 'bypassed safety checks' warning for mods using the new `Specialised.LoadStageChanged` event in 2.10.
+  * Deprecated `EntryDll` values whose capitalisation don't match the actual file. (This works on Windows, but causes errors for Linux/Mac players.)
 
 ## 2.10.1
 Released 30 December 2018 for Stardew Valley 1.3.32.
diff --git a/src/SMAPI/Framework/ModLoading/ModResolver.cs b/src/SMAPI/Framework/ModLoading/ModResolver.cs
index 835b0a54..a8564524 100644
--- a/src/SMAPI/Framework/ModLoading/ModResolver.cs
+++ b/src/SMAPI/Framework/ModLoading/ModResolver.cs
@@ -137,12 +137,23 @@ namespace StardewModdingAPI.Framework.ModLoading
                         }
 
                         // invalid path
-                        string assemblyPath = Path.Combine(mod.DirectoryPath, mod.Manifest.EntryDll);
-                        if (!File.Exists(assemblyPath))
+                        if (!File.Exists(Path.Combine(mod.DirectoryPath, mod.Manifest.EntryDll)))
                         {
                             mod.SetStatus(ModMetadataStatus.Failed, $"its DLL '{mod.Manifest.EntryDll}' doesn't exist.");
                             continue;
                         }
+
+                        // invalid capitalisation
+                        string actualFilename = new DirectoryInfo(mod.DirectoryPath).GetFiles(mod.Manifest.EntryDll).FirstOrDefault()?.Name;
+                        if (actualFilename != mod.Manifest.EntryDll)
+                        {
+#if SMAPI_3_0_STRICT
+                            mod.SetStatus(ModMetadataStatus.Failed, $"its {nameof(IManifest.EntryDll)} value '{mod.Manifest.EntryDll}' doesn't match the actual file capitalisation '{actualFilename}'. The capitalisation must match for crossplatform compatibility.");
+                            continue;
+#else
+                            SCore.DeprecationManager.Warn(mod.DisplayName, $"{nameof(IManifest.EntryDll)} value with case-insensitive capitalisation", "2.11", DeprecationLevel.Info);
+#endif
+                        }
                     }
 
                     // validate content pack